function salert(str) {
	var msgw, msgh, bordercolor;
	msgw = 400;// 提示窗口的宽度
	msgh = 100;// 提示窗口的高度
	titileheight = 25;// 提示窗口标题高度
	bordercolor = "#336699";// 提示窗口的边框颜色
	titlecolor = "#99ccff";// 提示窗口的标题颜色

	var swidth, sheight;
	swidth = document.body.offsetWidth;
	sheight = document.body.offsetHeight;
	if (sheight < screen.height) {
		sheight = screen.height;
	}

	var bgobj = document.createElement("div");
	bgobj.setAttribute("id", 'bgdiv');
	bgobj.style.position = "absolute";
	bgobj.style.top = "0";
	bgobj.style.backgroup = "#777";
	bgobj.style.filter = "progid:dximagetransform.microsoft.alpha(style=3,opacity=25,finishopacity=75";
	bgobj.style.opacity = "0.6";
	bgobj.style.left = "0";
	bgobj.style.width = swidth + "px";
	bgobj.style.height = sheight + "px";
	bgobj.style.zindex = "10000";
	document.body.appendchild(bgobj);

	var msgobj = document.createelement("div")
	msgobj.setattribute("id", "msgdiv");
	msgobj.setattribute("align", "center");
	msgobj.style.background = "white";
	msgobj.style.border = "1px solid " + bordercolor;
	msgobj.style.position = "absolute";
	msgobj.style.left = "50%";
	msgobj.style.top = "50%";
	msgobj.style.font = "12px/1.6em verdana, geneva, arial, helvetica, sans-serif";
	msgobj.style.marginleft = "-225px";
	msgobj.style.margintop = -75 + document.documentelement.scrolltop + "px";
	msgobj.style.width = msgw + "px";
	msgobj.style.height = msgh + "px";
	msgobj.style.textalign = "center";
	msgobj.style.lineheight = (msgh - titleheight) + "px";
	msgobj.style.zindex = "10001";

	var title = document.createelement("h4");
	title.setattribute("id", "msgtitle");
	title.setattribute("align", "right");
	title.style.margin = "0";
	title.style.padding = "3px";
	title.style.background = bordercolor;
	title.style.filter = "progid:dximagetransform.microsoft.alpha(startx=20, starty=20, finishx=100, finishy=100,style=1,opacity=75,finishopacity=100);";
	title.style.opacity = "0.75";
	title.style.border = "1px solid " + bordercolor;
	title.style.height = "18px";
	title.style.font = "12px verdana, geneva, arial, helvetica, sans-serif";
	title.style.color = "white";
	title.style.cursor = "pointer";
	title.innerhtml = "关闭";
	title.onclick = function() {
		document.body.removechild(bgobj);
		document.getelementbyid("msgdiv").removechild(title);
		document.body.removechild(msgobj);
	}
	document.body.appendchild(msgobj);
	document.getelementbyid("msgdiv").appendchild(title);
	var txt = document.createelement("p");
	txt.style.margin = "1em 0"
	txt.setattribute("id", "msgtxt");
	txt.innerhtml = str;
	document.getelementbyid("msgdiv").appendchild(txt);
}